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CHECKOUT
CALIBRATION
1. Verify that the unit is mounted in the correct position.
2. Verify appropriate input signal and supply voltage.
3. Verify appropriate configuration range.
Caution: Never connect 120 VAC to these transducers. Never
connect AC voltage to a unit intended for DC supply.
Transducer
Operation
This is a rough functional check only.
1. Adjust the pressure to obtain maximum output signal for
appropriate range.
2. Output should be 20 mA or 5 or 10 VDC.
3. Adjust the pressure to obtain minimum output signal.
4. Output should be 4 mA or 0 VDC.
Calibration of PX274/275/277/278 mA Units
1. Connect terminals [+] and [-] to the appropriate power
source.
2. Connect the DVM in series on the [-] terminal.
3. Apply low pressure to the unit. If configured for
uni-direction, adjust Zu trimmer to achieve desired low
output. If configured for bi-direction, adjust Zb trimmer to
achieve desired low output.
4. Apply high pressure to the unit and adjust span trimmer [S]
to obtain the desired high output pressure.
5. Repeat steps 3 and 4 until desired calibration is achieved.
All units are factory calibrated to meet or exceed published
specifications. If field adjustment is necessary, follow the
instructions below.
MAINTENANCE
Regular maintenance of the total system is recommended to
assure sustained optimum performance.
FIELD REPAIR
None. Replace with a functional unit.
Calibration of PX274/275/277/278 VDC Units
1. Connect terminals [+] and [-] to the appropriate power
source. The [-] terminal is also the negative output terminal.
2. Connect the DVM on DC volts across [O] and [-] terminal.
3. Apply low pressure to the unit. If configured for
uni-direction, adjust Zu trimmer to achieve desired low
output. If configured for bi-direction, adjust Zb trimmer to
achieve desired low output.
4. Apply high pressure to the unit and adjust span trimmer [S]
to obtain the desired high output pressure.
5. Repeat steps 3 and 4 until desired calibration is achieved.
Figure 7 - PX274/275/277/278 Low Pressure Transducer Dimensions shown in
millimeters and (inches).
40
(1.56)
54
(2.12)
S1 S2
ON
ON
MAMAC
9280
Z
Zb
S
127 (5.00)
57
(2.25)
114 (4.50)
28
(1.12)
28
(1.12)
140 (5.50)
76 (3.00)76 (3.00)
83
(3.25)
63.5
(2.50)
102
(4.00)
127 (5.00)
56
(2.20)
152 (6.00)
NOTE: The PX274/275/277/278 is a highly accurate device.
For applications requiring a high degree of accuracy, the use
of laboratory quality meters and gauges are recommended.
Enclosure
For Technical / Application Assistance call your nearest office
Servicing North America:
U.S.A.: Omega Engineering, Inc., One Omega Drive, P.O. Box 4047
Stamford, CT 06907-0047 USA
Toll-Free: 1-800-826-6342 (USA & Canada only)
Customer Service: 1-800-622-2378 (USA & Canada only)
Engineering Service: 1-800-872-9436 (USA & Canada only)
Tel: (203) 359-1660 Fax: (203) 359-7700
For Other Locations Visit omega.com/worldwide
omega.com info@omega.com
The information contained in this document is believed to be correct, but OMEGA accepts no liability for any
errors it contains and reserves the right to alter specifications without notice.
WARRANTY/DISCLAIMER
OMEGA ENGINEERING, INC. warrants this unit to be free of defects in materials and workmanshipfor a
period of 13 months from date of puchase. OMEGA’s WARRANTY adds an additional one (1) month
graceperiod to the normal one (1) year product warranty to cover handling and shipping time. This ensures
that OMEGA’s customers receive maximum coverage on each product.
If the unit malfunctions, it must be returned to the factory for evaluation. OMEGA’s Customer Service
Department will issue an Authorized Return (AR) number immediately upon phone or written request. Upon
examination by OMEGA, if the unit is found to be defective, it will be repaired or replaced at no charge.
OMEGA’s WARRANTY does not apply to defects resulting from any action of the purchaser, including but not
limited to mishandling, improper interfacing, operation outside of design limits, improper repair, or
unauthorized modification. This WARRANTY is VOID if the unit shows evidence of having been tampered
with or shows evidence of having been damaged as a result of excessive corrosion; or current, heat, moisture
or vibration; improper specification; misapplication; misuse or other operating conditions outside of
OMEGA’s control. Components in which wear is not warranted, include but are not limited to contact points,
fuses, and triacs.
OMEGA is pleased to offer suggestions on the use of its various products. However, OMEGA
neither assumes responsibility for any omissions or errors nor assumes liability for any damages
that result from the use of its products in accordance with information provided by OMEGA,
either verbal or written. OMEGA warrants only that the parts manufactured by the company will
be as specified and free of defects. OMEGA MAKES NO OTHER WARRANTIES OR REPRESENTA-
TIONS OF ANY KIND WHATSOEVER, EXPRESSED OR IMPLIED, EXCEPT THAT OF TITLE, AND ALL
IMPLIED WARRANTIES INCLUDING ANY WARRANTY OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. LIMITATION OF LIABILITY: The remedies of
purchaser set forth herein are exclusive, and the total liability of OMEGA with respect to this
order, whether based on contract, warranty, negligence, indemnification, strict liability or
otherwise, shall not exceed the purchase price of the component upon which liability is based.
In no event shall OMEGA be liable for consequential, incidental or special damages.
CONDITIONS: Equipment sold by OMEGA is not intended to be used, nor shall it be used: (1) as a “Basic
Component” under 10 CFR 21 (NRC), used in or with any nuclear installation or activity; or (2) in medical
applications or used on humans. Should any Product(s) be used in or with any nuclear installation or activity,
medical application, used on humans, or misused in any way, OMEGA assumes no responsibility as set forth
in our basic WARRANTY/DISCLAIMER language, and, additionally, purchaser will indemnify OMEGA and
hold OMEGA harmless from any liability or damage whatsoever arising out of the use of the Product(s) in
such a manner.
RETURN REQUESTS / INQUIRIES
Direct all warranty and repair requests/inquiries to the OMEGA Customer Service Department. BEFORE
RETURNING ANY PRODUCT(S) TO OMEGA, PURCHASER MUST OBTAIN AN AUTHORIZED RETURN (AR)
NUMBER FROM OMEGA’S CUSTOMER SERVICE DEPARTMENT (IN ORDER TO AVOID PROCESSING
DELAYS). The assigned AR number should then be marked on the outside of the return package and on any
correspondence. The purchaser is responsible for shipping charges, freight, insurance and proper packaging
to prevent breakage in transit.
FOR WARRANTY RETURNS, please have the following
information available BEFORE contacting OMEGA:
1. Purchase Order number under which the product
was PURCHASED,
2. Model and serial number of the product under
warranty, and
3. Repair instructions and/or specific problems
relative to the product.
OMEGA’s policy is to make running changes, not model changes, whenever an improvement is possible. This
affords our customers the latest in technology and engineering. OMEGA is a registered trademark of OMEGA
ENGINEERING, INC.
© Copyright 2015 OMEGA ENGINEERING, INC. All rights reserved. This document may not be copied,
photocopied, reproduced, translated, or reduced to any electronic medium or machine-readable form, in whole
or in part, without the prior written consent of OMEGA ENGINEERING, INC.
FOR NON-WARRANTY REPAIRS, consult OMEGA
for current repair charges. Have the following
information available BEFORE contacting OMEGA:
1. Purchase Order number to cover the COST of
the repair,
2. Model and serial number of the product, and
3. Repair instructions and/or specific problems
relative to the product.
PX274/275/277/278 Series
LOW PRESSURE SENSORS